Automated Teller Machine (ATM) Also called a CASH POINT, a combined computer terminal and cash dispensing machine connected via a WAN to a bank's central computers, that enables customers to make cash withdrawals and inspect account details from public sites such as streets, airports, shops and petrol stations. ATMs typically provide a small display screen that presents menus to the user, surrounded by a small number of buttons to make menu selections, and a numeric keypad for entering the customer's PIN number - the latter is checked against that stored on the customer's cash card, which must be inserted into a slot as a means of AUTHENTICATION.

ATMs are not DUMB TERMINALS, but self contained computers with their own local processing power, which makes the worldwide ATM network perhaps the most successful and reliable example so far of DISTRIBUTED computing: it is possible to withdraw cash from one's home account in countries right across the world, often using ATMs belonging to a different bank.